DK32

Directly heated battery heptode designed as the oscillator-mixer frequency changer in portable superheterodyne receivers. Its low filament consumption and modest electrode currents reflect economical battery-powered radio service.

Directly heatedCold cathodeCommon cathodeDissimilar

Sections: 1
Base: -
Socket code: IO
Base pins: 8
Nominal heater: 1.4 V / 50 mA

Description

The Mullard DK32 is a directly heated heptode intended primarily as a frequency changer in battery-operated receivers.

Socket description

International Octal

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base: -
Socket code: IO
Base pins: 8
Nominal heater voltage: 1.4 V
Nominal heater current: 50 mA
Parallel heater voltage: -
Parallel heater current: -
Series capable: No

Terminal pinout

Electrical assignments shared by every tube using this base designation.

No verified pinout is recorded for this base designation.

Section ratings

1 physical section, each with unique specifications.

Section 1

Heptode

X-ray radiationInterelectrode capacitances

Plate resistance: 600000 Ω
Max plate voltage: 90 V
Max screen voltage: 45 V
Max cathode current: 2.5 mA

Published ratings and characteristics promoted semantically from the approved source; repeated identical physical sections compressed where applicable.

Source-dependent data

Operating conditions by source

Each block preserves the test conditions and published values from one reference. Values from different sources are intentionally kept separate.

Data set 01

1951 Mullard Valve and Service Manual

Published operating points and test conditions from this source.

SECTION 1

Heptode

Other

Plate Voltage
90 V
Screen Supply Voltage
45 V
Plate Current
0.6 mA

Characteristic

Conversion Conductance
350 µS
Plate Resistance
600000 ohm

Data set 02

1963 Mullard

Published operating points and test conditions from this source.

SECTION 1

Heptode

Characteristics

Filament Voltage
1.4 V
DCOnly
Filament Current
80 mA
DCOnly
Plate Resistance
600000 ohm
Representative
Conversion Transconductance
250 uS
Representative
Oscillator Transconductance
550 uS
OscillatorSection

Other

Plate Voltage
90 V
FrequencyChanger
Screen Voltage
45 V
FrequencyChanger
Oscillator Anode Voltage
90 V
FrequencyChanger
Plate Current
0.6 mA
FrequencyChanger
Screen Current
0.7 mA
FrequencyChanger
Oscillator Current
1.2 mA
FrequencyChanger
Grid Current
35 uA
FrequencyChanger
Total Cathode Current
2.5 mA
FrequencyChanger
Maximum Plate Voltage
110 V
Maximum Screen Voltage
110 V